1. Field of the Invention
The present invention relates to a paper feed control system in a printer such as a typewriter and, more particularly, to a manual fine feed control system which ensures a fine feed in a manual paper feed mode of operation without a complicated mechanical structure.
2. Description of the Prior Art
A paper feed system in a printer, especially a typewriter, generally includes a platen for supporting a recording paper sheet. The platen is mechanically connected to a paper feed drive motor such as a pulse motor via a transmission gear mechanism. The platen is driven to rotate by the paper feed drive motor so that the recording paper sheet mounted on the platen is fed forward or backward (reverse) to position the recording paper sheet at a desired position.
In such a paper feed system, a manual paper adjusting is often conducted before or between the automatic paper feed operation. In the manual paper feed operation, the platen is manually rotated to precisely locate the recording paper sheet at a desired position. On the other hand, an electrical detent operation is conducted to determine the paper sheet position in the automatic paper feed operation. In the conventional system, the above-mentioned manual paper feed operation is not properly correlated with the electrical detent operation in the automatic paper feed operation and, therefore, an accurate paper sheet positioning is not ensured if a manual paper adjusting is conducted before the automatic paper feed operation.